Window sealant question

[cla6665]

Hi all, after a storm I noticed that some water is leaking in one of my fixed portlights.Boat is old and I just decided to reseal them all.
What kind of sealant do you suggest?
Thank you

[UYA]

I haven't done it myself but I enjoyed watching the guy from boatworks today how to replace and seal fixed port lights. Maybe they help you too?


https://www.boatworkstoday.com/video...ew-portlights/
https://www.boatworkstoday.com/video...ed-portlights/


Disclaimer: I have nothing to do with boatworkstoday other than I like to watch the videos.


Cheers Patrick

[tkeithlu]

Past threads may help, but be prepared for lengthy discussions. Preferences split between butyl tape and silicone sealant. My bet is that if the fit is close, with not gaps to fill, tape is the choice. Tape won't fill a gap. If you use sealant, be sure that it's not permanent (i.e. 3M 5200), and buy stuff that is rated for thirty years. That rating is a measure of the amount of water not in the goo, hence a measure of not contracting as it sets. In any case, make sure that there is not a way for water to get into the core between the inner and outer fiberglass, which is another topic of tales of woe.

I hope that your project goes very well.

[dcstrng]

Originally Posted by cla6665

Hi all, after a storm Boat is old and I just decided to reseal them all.
What kind of sealant do you suggest?
Thank you

Yep I have a similar -- the owner before me (about 3-4 years ago) put in new fixed "windows" but they leak in the rain... am looking for a solution that doesn't involve removing a gazzillion fastreners and buys me a year or so as i have hull issues to remedy first...

Any old farm remedies would be useful -- eventually I'll need to remove and rebed, but for now am just looking for a stop-gap...

[Discovery 15797]

I used 3/8" round butyl from New Found Metals. It is softer and better than butyl tape IMHO, but a bit messy to work with, and will fill small gaps. It's a chore to clean up

The benefit of butyl over a sealant is that it will not separate from expansion or contraction, or torsion which is the cause of most leaks for ports or windows using sealants.

The down side of butyl is that it is very susceptible to chemicals and some cleaners.